Influence of salinity-decreasing regimes on survival of juvenile Argopecten irradians

Three salinity-decreasing regimes were designed to study the tolerance of Argopecten irradians to salinity. The 3 regimes were:Ⅰa decrease of 1 salinity per day;Ⅱa decrease of 3 salinity per day;Ⅲ a decrease of 3 salinity per day when the salinity was above 19 and a decrease of 1 salinity per day when salinity was below 19. The results showed that the scallop tolerance to salinity was the greatest in group Ⅰ with a low salinity limit of 8 and the smallest tolerance appeared in group Ⅲ. The electronic microscope observation showed that the gill and the liver were both damaged badly under the stress of low salinity. So the salinity of shrimp-scallop polyculture water should be above 10 with a fluctuating range within 3.